While configuring the synthetic containment core of an interstellar probe, an engineer programs a virtual nitrogen atom with seven electrons arranged as $1s^2 2s^2 2p_x^2 2p_y^1 2p_z^0$. The diagnostic terminal immediately flags this arrangement as an invalid ground-state candidate that violates quantum orbital filling guidelines. Which principle or rule was directly violated in the distribution of the $2p$ electrons for the ground state?

A) The Aufbau principle, because the higher-energy $3s$ subshell remained unpopulated while pairing occurred in the $2p$ subshell.

B) Hund's rule, because degenerate orbitals within the $2p$ subshell must each be singly occupied with parallel spins before electron pairing begins.

C) The Pauli exclusion principle, because an individual orbital is fundamentally forbidden from holding two electrons with opposite spins.

D) The Aufbau principle, because the $2s$ orbital must remain half-filled until all degenerate $2p$ orbitals have reached double occupancy.

Aufbau principle, Pauli exclusion principle and Hund's rule Original Scenario-Based Download PDF

Chemistry · Atomic Structure · Chemistry · Electrons in Atoms

1 Chemistry practice questions on Aufbau principle, Pauli exclusion principle and Hund's rule. Questions built around original scenarios.

Atomic Structure · Chemistry

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